1. Field of the Invention
This invention relates to a container for cell culture production, and more particularly to a roller bottle having axial pleats for increasing cell growth surface area and circumferential ribs for reinforcing the bottle walls.
2. Description of Related Art
One type of container commonly used in the laboratory for culturing of cells is known as a “roller bottle”. Roller bottles are generally cylindrically shaped and are adapted to rotate about their axes. The internal surfaces of such roller bottles are for providing active surfaces for cells. A liquid growth medium is introduced into the roller bottle. The rotating movement of the bottle keeps the internal surfaces wetted with a liquid medium, thereby encouraging the growth of cells. Rotating rollers of an appropriate apparatus are employed to rotate these roller bottles.
It is desirable to grow large amounts of cells, mostly for cell by-products, such as pharmaceutical substances that are secreted by cells. Various approaches have been used in order to increase the surface area internally of roller bottles. One approach has been to increase the amount of actual surface area available for cells to grow on.
For example, roller bottles produced as a unitary structure by a blow-molding technique are known that include longitudinal pleats formed in the walls of the roller bottle. These longitudinal pleats increase the effective surface area internally of the roller bottle. The pleats extend into the growth chamber for the purpose of increasing culture or cell yield.
It is further known to provide a culture vessel having such longitudinal pleats, and further including circumferential collars which encircle the external surface of the top and bottom end of the vessel. These collars are for the purpose of maximizing the vessel's grip point when the vessel is placed on its side on the rollers of a rotating apparatus.
The prior art also discloses a roller bottle having pleats cross-wise to the axis of the bottle for increasing the surface area for growing cells and further including at least one unpleated longitudinal drain panel, and axial reinforcing ribs along the outer edge of the cross-wise corrugation for strengthening the pleated bottle.
It is also known to use circumferential ribs on a roller bottle for the purpose of reinforcing the bottle walls. In this regard, the prior art discloses a roller bottle having flexible plastic walls and a plurality of spaced-apart circumferential reinforcement rings defined in the flexible plastic walls to cause the body to retain a generally cylindrical shape.
A problem associated with prior art roller bottles, especially those having pleats with the purpose of expanding the surface area for growing cells, has been the tendency of the bottle walls to expand when the insides of the bottles become pressurized. This causes the bottle to stop rolling on its roller rack. This is problematic because in the absence of the rotating movement, a portion of the internal surfaces becomes dry, promoting cell death in these areas.
It is desirable therefore to provide a pleated roller bottle which is reinforced so as to add rigidity to the vessel wall to prevent the bottle from expanding to the point where the roller bottle stops rolling.